
# Authors:
#     Loic Gouarin <loic.gouarin@polytechnique.edu>
#     Benjamin Graille <benjamin.graille@math.u-psud.fr>
#
# License: BSD 3 clause

"""
Example of a D2Q4 for advection
"""
import sympy as sp
import pylbm
u, X, Y = sp.symbols('u, X, Y')

d = {
  'dim':2,
  'scheme_velocity':1.,
  'schemes':[{
    'velocities': [1, 2, 3, 4],
    'conserved_moments':u,
    'polynomials': [1, X, Y, X**2-Y**2],
    'equilibrium': [u, .1*u, .2*u, 0.],
    'relaxation_parameters': [0., 1.9, 1.9, 1.4],
    },
  ],
}
s = pylbm.Scheme(d)
print(s)
